StrSet.hs

-- | A set of strings to match.
module Graphics.Text.Font.Choose.StrSet(StrSet(..), module S, validStrSet) where

import Data.Set (Set)
import qualified Data.Set as S

import Data.MessagePack (MessagePack(..))
import Test.QuickCheck (Arbitrary(..))

newtype StrSet = StrSet { unStrSet :: Set String } deriving (Eq, Show, Read)

instance MessagePack StrSet where
    toObject = toObject . S.toList . unStrSet
    fromObject msg = StrSet <$> S.fromList <$> fromObject msg
instance Arbitrary StrSet where
    arbitrary = StrSet <$> S.map (filter (/= '\0')) <$> arbitrary

validStrSet :: StrSet -> Bool
validStrSet (StrSet self) = notElem '\0' `all` self